Portable bending machine



Oct. 2, 1951 Filed June 1. 1948 E. T. TAL

PORTABLE BENDING MACHINE 3 Sheets-Sheet 1 INVENTOR.

411M Jib/ways Oct. 2, 1951 TAL PORTABLE BENDING MACHINE 3 Sheets-Sheet 2 Filed June 1. 1948 INVENTOR [a ae/'1 7 5/ )Z'hrneys Oct. 2, 1951 E. T. TAL

PORTABLE BENDING MACHINE Filed June 1. 1948 3 Sheets-Sheet 5 INVENTOR.

Patented Oct. 2, 1951 UNETED STATES PATENT OFFICE PORTABLE BENDING MACHINE Edward T. Tal, Milwaukee, Wis.

Application June 1, 1948, Serial No. 30,251

9 Claims. 1

This invention relates to a portable bending machine and particularly has reference to a bending machine employed in the cold bending by hand to tubes and pipes of generally small diameter such as are employed in radiant heating installations.

One object of the invention is to provide a generally light-weight bending machine readily port able from place to place and which is held in place in service by the weight of the operator.

Another object is to provide a bending machine which can be used in a horizontal or vertical position on a floor or work bench.

Another object of the invention is to provide a bending machine from which the tube or pipe is readily released after bending.

Another object is to provide a bending machine in which the ring gear is protected from injury under rough handling.

Another object is to provide a bending machine which can be employed to bend tubes or pipes on the floor close to a wall of a room.

A further object is to provide a bending machine readily adjustable to bend tubes and pipes of different diameters.

Another object is to provide a bending machine for bendingv tubes and pipes to different radii of bend.

A further object is to provide a tube bender with a readily adjustable guide or clamp for different diameter of tube and pipe for initially guiding the same to be bent.

Another object is to provide a portable tube bender which can be laid on the floor in service and operated by the operator in a standing position.

Another object is to provide a bending machine which may be employed to bend a tubular member to the right or left.

These and other objects of the invention Will appear hereinafter in connection with the following description of the drawing illustrating an embodiment of the invention.

In the drawing:

Figure 1 is a top plan view of the bending machine of the invention close to the wall of a room with a tubular member bent to a 90 angle;

Fig. 2 is a longitudinal sectional view taken on line 2-2 of Figure 1;

Fig. 3 is a side elevational view of the bending machine with the tubing released after bending;

Fig. 4 is a section taken transversely of the bender on line 4-4 of Fig. 2;

Fig. 5 is a detail side elevational view of the clamp or guide of the bending machine with a tube clamped in place for bending;

Fig. 6 is a detail sectional view taken on line 6'6 of Fig. 2;

Fig. 7 is a top plan view similar to Figure 1 with a larger diameter tubular member bent to a 180 angle and illustrating a former shoe of lesser diameter than the shoe in Figure 1;

Fig. 8 is a detail view taken on line 8-8 of Fig.7; and

Fig. 9 is a view with a bending machine as in Figure 1 with the bender adjusted to make a left hand bend of 135.

In general, the invention is directed to a bending machine which can be laid on a floor or bench and has a base member of a construction to be employed by the operator to hold the machine in place in service. The base supports a former shoe against which is bent a tube or pipe by a pivotal freely rotating roller wheel driven around the former shoe by a block and gear assembly. The entire unit is subject to various adjustments for handling tubes or pipes of diiferent diameter and for bending them to different radii and angles of bend and is compact and portable so that it may be transported from place to place and be utilized on the floor to bend tubing close to the wall of a room.

Referring to the drawings the portable bending machine illustrated has a flat, elongated base i which rests on the floor 2 and is of sufficient width, length and strength to support a man standing or kneeling thereon to prevent it from sliding on the floor in service. The forwardly projecting plate 3 is secured across the forward end of base I and supports the upstanding stub shaft 4 which is Welded to plate 3 andreceives the forming assembly to be described.

The semi-circular former shoe is mounted on shaft 4 above base plate 3 and comprises a shank 5 which rests on a shoulder 6 of shaft 4 to space the shoe from the base, and an outer former rim I connected to the shank by a relatively thin web 8. The periphery of former rim 1 has a circumferentially extending semi-circular groove. A plurality of circumferentially spaced holes are provided in web 8 to register with the short pin 9 which is located directly forward of stub shaft 4 and is welded to base plate 3. Pin 9 secures the former shoe against rotation in the angular position of the shoe desired depending upon the hole in web 8 with which pin 9 is registered.

The shank 5 of the former shoe projects upwardly from the shoe to receive the hub ID of the ring'gear and axially spacethe body portions of the ring gear and former shoe when the ring gear is assembled on stub shaft 4 directly above the former shoe. Hub ll] of the ring gear projects upwardly around shaft 4 from the gear proper to a circumferential line slightly spaced from the upper end of stub shaft 4 and overhangs shank of the former shoe.

Ring gear hub I0 is connected to the peripheral upturned rim II of the gear by a generally thin web |2 which isprovided with a plurality of holes registering with pin 9 to locate the ring gear in different angular position corresponding to those of the former shoe. generally semi-circular shape similar to the former shoe.

The inside of the rim II has a plurality of teeth l3 to provide the ring gearasa rack, the use of which will be described hereinafter.

lhe ring gear also is of "a.

A slide block of generally rectangular shape-lis mounted on stub shaft '4 above the ring gear and :comprises a frame 14 within which is welded the rear bushing l5 and the forward bushing .|6.

Bushing |5 is pivotally mounted on stub shaft 4 around the ring gear hub l0 and the lowerend portion of the bushing projects downwardly from frame M to rest on a shoulder of the ring gear and axially space the body portion of the ring gear and slide block apart. The washer :H .is assembled over the upper end of shaft 4 against bushing l5 and cotter key I8 extends through shaft 4 across washer IT to keep the assembly from axially moving'ofi shaft 4.

Outer bushing l6 of the slide blockoverhangs the rim H of the ring gear and the pinion I9 is disposed therein for rotation. The lower end of pinion I-B rests on web |-2of the ring gear and the exterior of'pinion '|9 approaching the lower-end is provided with pinion teeth which mesh 'with teeth l3-on the rim ll of the ring gear to ride around'the gear on the inside of rim upon rotation-of the pinion. The square headfl] is provided on'the upper end-of pinion :|9abov.e-.bushing -|6 for engagement by the handle 2| -so the operator can rotate the pinion around the 'gear rack, as for-example from a standing position, .and efiect'rotary motion of theslide block. The

handle 2| shown as broken in Fig. 3 is of a length so that the operator can rotate the pinion while standing on the-elongated portion of'base The handle 22'is welded to bushings |5 and|6 of the slide block to facilitate lifting .the *tube bender from place to place.

-A slide member formedpf a rectangular :frame having side "members -23 is assembled with the slide blockand is freeto slide transversely thereof inwardly and outwardly of the block tonumerous positions, and is of a lengthto extend outwardly from theihlock a substantial distance. A horizontal hole isprovided in bushing |5 and a rpluralityof spaced registering holes are-.provided in the side'members 23 of the frame toreceivethe itaperedpin ze and'lock the frame-in a'number of fixed positions relative to the "slide "block. .Chain .25 secures 'thehead of pinZG to the slide Lblock to prevent the pin from being lost.

-A-depending sleeve or "bushing is securedwithinthe outer overhanging end of the sliding frame to receivethe shaft 26 of theroller wheel 2?, and the unit is prevented "from dropping from the sleeve byzthe cotter pin28 which extends trans- *versely through the upper end of shaft 26. The

wheel freelyrotateson shaft 26.

The :s'hank of-roller wheel'ZTis connected by a plurality of spokes 29 to the rim 30 0f:the Wheel Which-has asemi-circular groove in the periphery formed complementary to the groove in rim 1 of the former shoe so that the tube 3| which is bent by the bending machine can be received between the respective rims of the shoe and roller wheel.

Tube 3| after bending is released from the circular groove between rim 1 of the former shoe and rim 30 of the roller wheel by removal of tapered pin 24 from the registering holes in the slide block and sliding the frame outwardly from the block to separate the respective rims of the former shoe and roller wheel. When freed from the rims the tubing drops to the floor or bench and the bender can be lifted and moved to another-spot for further bending operations.

A guide attachment is also provided with the bender to insure that the tube 3| will properly enter .the circular groove between the former shoe and roller wheel and be prevented from slipping therebetween. The guide mechanism has a cross-plate 32 which extends transversely across base plate 3 to ,the-rear-of stub shaft 4.

Plate .32 .has a :plurality of :spaced holes which register with the spaced dowels .33 extending upwardly from base plate 3 and a hole inplate 3 between the dowels into which is threaded the thumb screw 34. The cross-plate .32 may be moved to several transverse positions for bending tubes or pipes-to different radii. The dowels 33keep theplate 32 from pivotingand-thethumb screw holds it'down against plate 3.

The outer end of cross-plate 32 has .an abutment '35 which vis'engaged by the tube .3| to'be bent. The U-clamp '36 which ,-has a handle 37 is located across the abutment :35 and tube so that one legof the clamp-engages thetubeland the other leg overlapsthe abutment 35 to-clamp the tube to the abutment to guidethe'tube 3| for entrance into the circular groove between the rims of the former shoe vand roller .wheeleand prevent the tube from slipping during the bendingoperation. U-clamp-Sfi is quicklyliftedfrom engagement with the abutment and tube torelease the tube after the :bending operation is completed. Cross-plate 32 -may also'bereversed in position by the operator -'for .use in making right or left hand bends with the machine. The U-cIamp. 3.6 ischangedin bendingdifferent diameter of tubes or pipe as will be described. 4

As anexample of .theoperation of thebender, thedevice isfirst laid on-thefloor andthe roller wheel .21 is rotated relative totheformer shoe-to the starting positionfor beginning the operation which .is designated 0 in Figure 1.. Tube 3| is then placed inthe circulargroove formed between rim 1 of the former shoe and the ..rim .30 of the roller wheel and the roller wheel is clamped securelyagainst the former shoeby inserting tapered pin 24 in registering holes .in the'slide block and the slide frame.

Thereafter the .tube 3| is held against abutment 35 and U-clamp 36 is clamped by the .operator over the abutment and tube to grip the tube therebetween and index it relative to the circular groove between the former shoe and roller wheel. The clamp also'binds the tube to the former shoe and prevents the'tube from slippin during the bending operation.

The operator then engages head 20 of pinion t9 with a wrench or crank or the long handle 2|, and pinion I9 is rotated on gear teeth l3 to rotate roller wheel 27 around the grooved rim 1 of the former shoe through the slide block and the frame from which the roller wheel 27 is suspended.

The tubing may be bent to any'angle on the former shoe shown up to 200". m the drawings angles of 45, 90, 135 and 180 are designated J on the machine in both directions in Figure 1 for purposes of illustration. The rotation of the roller wheel is stopped at the desired angle of bend. When the tubing is bent to the desired angle tapered pin 24 is withdrawn and the frame is moved outwardly of the slide block to separate the rim 30 of the roller wheel from the rim I of the former shoe and drop tubing 3| to the fioor or bench as in Fig. 3.

The ready removal of the tubing from the bender is an important feature of the invention and particularly finds use in radiant heating installations where the tubing is laid flat on the foundation or base of the floor and bent in a series of continuous shapes of 8 form. The tubing is quickly released and drops a mere matter of inches to the base from the bender so there is no danger of injury.

The bender of the invention is readily adaptable in bending pipe and tubing of different diameter and to different radii of bends.

The roller wheel 21 need only be changed for different diameters or size of pipe and tubing and the former shoe is changed to bend pipes and tubes of different size and also to bend pipes and tubes to different radii of bends. Thus, for example, by replacing roller wheel 21 and the former shoe with other roller wheels and shoes with grooves of different extent, pipes or tubes of one-quarter, three-eighths, one-half, fiveeighths, three-quarters, seven-eighths and one inch in diameter may each be bent to a radii of say two, three, four and one-half, six, and seven and one-half inches or even a larger radii.

By replacing only the former shoe with shoes of different diameter and using the same roller wheel, pipes, or tubes say of one-half inch diameter can be bent to two, three, four and a half, six or seven and one-half inches in radii. This is made possible by sliding the frame outwardly of the slide block to position roller wheel 2'! farther from stub shaft 4 and accommodate a former shoe of greater diameter therebetween. The U-clamp 36 is also changed to properly clamp pipes or tubes of different diameters.

A different former shoe is readily replaced simply by removing cotter key l8 and washer I! from the stub shaft 4 lifting off the slide block and the frame carrying the roller wheel 21 and slipping the ring gear, and shoe to be replaced off the shaft. The new former shoe is then mounted on the shaft 4, the ring gear is slipped in place followed by the slide block and the frame and the washer I! is placed over the shaft and cotter key I8 is then inserted through the upper end of the shaft 4 to secure the assembly in place.

When the former 1 is of smaller diameter than the gear H, the wheel 21, because of its large diameter, will lie partly under the ring gear in certain positions of the frame with respect to the slide block and will carry the ring gear with it when the frame and slide block are lifted from shaft 4.

The roller wheel 21 is simply replaced by removal of cotter pin 28 and mounting the shaft 25 of a new wheel in the sleeve on the end of frame 23 and inserting pin 28 in place. When the former shoe is changed to one of greater or lesser diameter the guide attachment must be adjusted to properly guide or index the tubing to be bent into the circular groove between the former shoe and roller wheel 21. In making this adjustment cap screw 34 is unthreaded to release cross-I'plate 32 from base plate 3 and the plate 32 is lifted from dowell 33 upon which it is assembled as in Figure 1 and shifted inwardly for example and mounted over dowels 33 as in Fig. 6. The thumb screw 34 is threaded home to hold plate 32 in place against plate 3, the dowell or dowels keeping the plate 32 from pivoting.

Figure 1 illustrates a right hand bend of a tube to and the bend has been made close to the wall indicated by the broken line 38.

In -Fig. 7 the tube 39 is shown as of greater diameter than the tube 3| in Figure 1 and a bend of lesser radii has been accomplished with the tube bent to 180. The former shoe is of lesser diameter and Fig. 8 illustrates the larger grooves in the shoe and roller wheel to receive the greater diameter tube 39.

In Fig. 9 the bender of Figure 1 has been adjusted to make a left hand bend of the tube 3| to a angle.

The, bender has a number of advantages over previouls pipe or tube benders. Itis of generally lightweight and readily portable from place to place'and can be used either on a floor or bench. In use on the floor a long handle is supplied to rotate the roller wheel. Very little effort or power is required to rotate the pinion around the ring gear so that hard or soft metal tubes or pipe of copper or steel may readily be bent. The teeth of the ring gear are fully protected against injury for hard use in service by locating them inside the rim of the gear ring.

By substituting a roller wheel of large diameter for the small roller usually employed a smoother bend is naturally obtained in pipes or tubes which are bent in the machine due to the lesser pressure per square inch. The large diameter wheel makes it possible to obtain adjustments for bending tubes or pipes to different radii without disturbing the power applied through the pinion and ring gear. The large wheel also aids in disassembling the bending machine to replace the former shoe when desired.

The bender can be used close to the wall for d a right or left hand bend and a tube is readily dropped from the member by separating the roller wheel from the former shoe as described.

The readly adjustment of the roller wheel outwardly and easy removal of the wheel and former shoe for substitution of other shoes and wheels of different size makes the bender available for bending numerous sizes of pipes and tubes and to be used in different places requiring different radii and angle of bend.

The U-shape guide clamp is also a simple inexpensive device for guiding the tube and pipe between the shoe and roller to be bent and it is readily removed, replaced by hand and adjusted in service. The clamp prevents the tube from slipping.

Various embodiments of the invention may be employed within the scope of the accompanying claims.

I claim:

1. A portable bending machine for bending a pipe 'or tube member in a substantially horizontal plane which comprises an elongated plate-like base adapted to rest upon the floor and tobe maintained in place during bending operations by an operator standing thereon, an upstanding shaft secured to said base adjacent one end thereof, a former shoe mounted on said shaft above the base and having a circumferentially extending rim with a groove therein of semicircular cross-section, a generally large size free- ;y :rot-ating roller wheel having a :circumferen- --tially ;-ext.e,nding rim radially aligned with the grimf saidshoe and-a groove in said rim-of semi-circular cross-section-comp1ementary to the -grooverin saidshoe'to provide a circular-groove .:,be,tween theroller wheel and-shoe to receive the member to be bent,means to supportsaid wheel from said'shaft for rotation around the former shoe, and meansmounted on saidfirst mentioned means, geared -to said shoe, andextendingsub- .-stantially vertically upwardly therefrom for accircular cross-section,=agenerally large size free- -;ly, rotating roller wheel having a'circumferentially:extending rimradially-aligned with the-rim of said shoe and agroove in said rim of semi circular cross-section complementary to the groove'in-saidshoe to-provide a circular groove betweenrthe roller 'wheel and shoe to receive the -member to be bent, means to support said wheel from said shaft for rotationaround theformer shoe, a .-stationary ring gear mounted on the shaft abovesaid former shoe with gear teeth provided circumferentially around the inside of the rim thereof, and a pinion projecting from said ,-means in engagement with said gear teeth .with-a head'on-the upper end for engagement by .avertically extending tool-for rotating the pinienand the supporting :means 'for said wheel to rotate,the wheeharoundsaid shoe and bend the member tothe angle desired. V v

..-3. A fportable bending maehine fort bending a .pipeor tube member-which comprises a base, an upstanding shaft secured .to said'base, aformer shoe mounted on said shaft above the base and (having ,a circumferentially extending rim with a groove inathe outer periphery thereof of semi-circular .GYOSS'rSBCtiOII, said former shoe being interchangeabl -with a former .shoe of difv.ferent-diameter to obtain: different radii of bends .in,members,- a ring gear mounted on the shaft .above said former shoe with gearteeth'provided circumferentially around the inside of the rim -tthereof a generallylargevdiameter rotating roller 1 wheel having .a circumferentially extending rim radially aligned with the rim of. said shoeand a groove .in said rim of. semi-circular cross-section complementary vto the groove in. said .shoe toprovi de a circulargroove between the roller .wheel ,and shoe to .receive .the member to be bent, ,a frame member pivoted on said shaft and supporting said wheel for rotation around the former shoe, and a pinion projecting from said frame me'mber in engagement with said gear teeth with semi-circular cross-section complementary to the groove in said shoe to provide1arcircular.groove between the roller wheel andshoe to receive-the member-to beibent,'a-slide block-pivotally mount- -ed on said shaft above the formershoe,-a-frame memberpomprising: spacedaside. members mounted inwthe sides of saidblock and projecting out- :wardlyr thereof 'to receive-the shaft-of said wheel 'atgtheouter :end ofsaid side, members, said-members being adapted to shift inwardly :and outwardly of the block to spacethe wheel-f-rom the shoe and 'releaserthe member bent between=the same and accommodate operation ;of th wheel with former shoes-of1di1ferent diameterfor ob- --taining different radii of bends,-and means to rotate the bloclgwfra-me and wheel around the sho on said shaft to bend the member to the an le :desired.

25. :Inga bending machine :for bending a pipe Ol tube member, a base, an upstanding shaft secured to said member, -a former shoe amounted :onsa-id shaft ab0v -the-base and comprising a shank assembled onithe shaft and :a circumferentia1ly extending rim having a semi-circular groove therein and :connected to the'sha-nk by a thin web having arplurality of;circumferentially spaced holes, a gear ring mounted onsaidshaft with a shank and outer rimconnected by a-thin web having "a plurality of circumferentially spaced holes therein corresponding to the holes ;in th web of the former shoe, andya short pin secured to the base of the machine and register- .ing with the holes'in-sai'd'shoe and ring :gear' to hold the same against rotationiin a number of diiferentangular positions.

6. A'bending machine for bending agenerally small diameter tubular member comprising a base, an upstanding shaft mounted thereon, a

peripherally grooved former :shoe mounted on said-shaft, a complementary formedroller wheel supported for pivotal-movement around said for- -mer-shoe, a stationary ring gear mounted on the :shaft above-said former shoe and having a rim with gearteeth provided circumferentially on the inside thereof, a frame member :mountedabove ,the'formershoe on the-shaftand supporting-the roller wheel therefrom-and a pinion mounted-in saidframe member and engaging the teeth of the ring gear to be rotated therearound when .engaged by -a vertically extending tool to pivot the frame and roller wheel around said shoe.

'7. In a bending machine for bending agen- .erally small diameter tubular member and having a rotatable peripheral grooved roller wheel pivoted around a complementary formed former shoe .the gear rack to drive theblock around on said shaft, and asliding frame supported by theslide block to slide inwardly and outwardly of said block and pivoting therewith and having the shaft of the freely rotating roller wheel mounted therefrom at the outer end, and a pin registering in holes in the frame and slide block to hold the frame and the roller wheel suspended there from in different radial positions as respects the former shoe mounted on the shaft.

8. In a bending machine for bending a generally small diameter tubular member and havin a rotatable peripheral grooved roller wheel pivoted around a complementary formed former shoe mounted upon a shaft, a base for supporting said shaft, a ring gear mounted on the shaft above th former shoe and having a gear rack around the inside of the circumferentially extending upstanding rim thereof, a slide block having an inner bushing mounted on the shaft above the ring gear and connected by side members to an outer bushing supporting a depending pinion therefrom in engagement with the gear rack to drive the block around on said shaft, and a handle welded to the inner and outer bushings of the slide block to facilitate lifting the machine from place to place.

9. A portable bending machine for bending a pipe or tube member in a substantially horizontal plane to different angles and radii of bend which comprises an elongated plate-like base adapted to rest upon the floor and to be maintained in place during bending operations by an operator standing thereon, an upstanding shaft secured to said base adjacent one end thereof, a former shoe mounted on said shaft above the base and having a circumferentially extending rim with a groove therein of semi-circular cross-section, a ring gear fixed to said shoe, a generally large size freely rotating roller wheel having a circumferentially extending rim radially aligned with the rim on said shoe and a groove in said rim of semi-circular cross-section complementary to the groove in said shoe to provide a circular groove between the roller wheel and shoe to receive the member t be bent, an extensible frame member pivotally mounted on said shaft to support said roller wheel and to shift the latter inwardly and outwardly of said shaft to space the wheel from the 10 shoe to release the member bent between the same and to accommodate operation of the wheel with former shoes of different diameter for obtaining different radii of bends, a stub shaft extending vertically through said frame member between the axis of said wheel and said shaft, and a pinion fixed on said shaft and geared to said ring gear to rotate the frame and wheel around the shoe by rotation of said shaft in order to bend the member to the angle desired, th upper end of said shaft being adapted for connection to operating means extending substantially vertically upwardly therefrom for access to the operator.

EDWARD T. TAL.

REFERENCES CITED The following references are of record in the file of this patent:

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